Parasitology Prelims

Balantidium coli Chilomastix mesnili Entamoeba coli Entamoeba histolytica Endolimax nana Giardia lamblia Iodamoeba butschlii Leishmania donovani

Balantadiasis Non pathogenic Non pathogenic Amoebiasis Non pathogenic Giardiasis Non pathogenic Visceral Leshmaniasis

Cyst Cyst Mature cyst Cyst Cyst Cyst Cyst Promastigote

ATRIAL FLAGELLATES - Lower forms of parasite - Completely unicellular - Asexual reproduction – Binary fission - Non pathogenic o Chilomastix mesnili - Pathogenic o Giardia lamblia

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Metronidazole INGESTION Metronidazole Stibogluconate Na

PARASITE: Balantidium coli, trophozoite  Only member of the ciliate group that is pathogenic to humans  Considered as the largest protozoan  ORGAN OF LOCOMOTION: CILIA  DEFINING CHARACTERISTIC is NUCLEAR DIMORPHISM o Micronucleus o Macronucleus INFECTIVE STAGE: CYST DIAGNOSTIC STAGE: TROPHOZOITE DISEASE: Balantidiasis MOT: INGESTION HABITAT: COLON LABORATORY: microscopic examination of stool and tissue sample POPULATION AFFECTED: TREATMENT: METRONIDAZOLE

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PARASITE: Leishmania donovani  Kala-Azar  Dum dum fever  Old world leishmaniasis  AMASTIGOTE infective to the vector  PROMASTIGOTE infective to humans INFECTIVE STAGE: PROMASTIGOTE DIAGNOSTIC STAGE: AMASTIGOTE DISEASE: VISCERAL LESHMANIASIS VECTOR: Phlebotomous sandfly DEFINITIVE HOST: Man and Mammals RESERVOIR: DOG EPIDEMIOLOGY:  Common in Africa, India and Asia (Particularly in the middle east) LABORATORY:  Cultivated in NNN or liquid cultures as promastigote of splenic and hepatic material  Blood smear or culture  Sternal, splenic, hepatic, or LN puncture TREATMENT: Stibogluconate sodium

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PARASITE: Chilomastix mesnili TROPHOZITE  Asymmetrically pear  With constricted middle part  Granular cytoplasm  With food vacuoles CYST  

Pear or lemon shaped With knob like protuberance

INFECTIVE STAGE: CYST DIAGNOSTIC STAGE: TROPHOZOITE LABORATORY DIAGNOSIS: STOOL EXAMINATION MOVEMENT:CORK SCREW LIKE MOVEMENT NO TREATMENT REQUIRED.

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TROPHOZOITE - DIAGNOSTIC STAGE - Seen in WATERY STOOL - Has 8 FLAGELLA - With a pair of nuclei - FALLING LEAF OTILITY - PEAR SHAPED - BINARY FISSION

CYST - INFECTIVE STAGE - With CONDENSED FLAGELLA (cannot be seen, folded, thick, exhibit no movement at all) - OVOID in shape - Young: 2 nuclei - Mature: 4 nuclei

PARASITE: Giardia lamblia DISEASE: GIARDIASIS INFECTIVE STAGE: CYST DIAGNOSTIC STAGE: TROPHOZOITES MOT: INGESTION DIAGNOSIS:  DIRECT FECAL SMEAR – identifying ova/adult  STOOL EXAM – complete examination of stool DRUG OF CHOICE: METRONIDAZOLE

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PARASITE: Endolimax nana  NON-PATHOGENIC  Flagellate  CYST o 7-10µm o Spherical, ovoid or ellipsoid o Mature cyst – 4 nuclei o Large blotlike karyosome and presence of peripheral chromatic (similar with trophozoite) o No chromatoid bar o GROUND GLASS APPEARANCE INFECTIVE STAGE: CYST DIAGNOSTIC STAGE: CYST OR TROPHOZOITE IN THE STOOL LABORATORY DIAGNOSIS: STOOL EXAMINATION NO TREATMENT REQUIRED.

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TROPHOZOITE - INVASIVE FORM (PATHOGENIC STAGE) - In LIQUID STOOL - 1 NUCLEUS - Pseudopod:active. progressive and directional movement - Centrally located karyosome: “Bulls-eye appearance” - With ingested RBC - With Charcot-Leyden crystals

CYST - INFECTIVE STAGE - In FORMED STOOL - 4 nuclei (quadrinucleated cyst) -  Resistant to gastric secretion - Cigar-shaped chromatoidal body - With glycogen mass

PARASITE: Entamoeba histolytica DISEASE: AMEOBIASIS INFECTIVE STAGE: CYST DIAGNOSTIC STAGE: 4 NUCLEI CYSTS OR TROPHOZOITES ON OVA AND PARASITE EXAM MOT: INGESTION LABORATORY DIAGNOSIS: STOOL EXAMINATION

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TROPHOZOITE - Motility: Sluggish, nonprogressive through blunt pseudopod - Single nucleus with large irregularly shaped karyosome that is ECCENTRICALLY LOCATED - Vacuoles often contain bacteria - In contrast to E. histolytica, RED BLOOD CELL INCLUSIONS ARE NOT PRESENT IN THE TROPHOZOITES OF E. COLI.

CYST - Spherical with thick cell wall - 1-8 NUCLEUS (E.histolytica – 1 to 4 nuclei only) - Cytoplasm contains glycogen mass - Thin chromatoid bars, often with pointed to splintered ends

PARASITE: Entamoeba coli DISEASE: NON PATHOGENIC INFECTIVE STAGE: MATURE CYST DIAGNOSTIC STAGE: CYST OR TROPHOZOITES ON OVA AND PARASITE EXAM MOT: INGESTION LABORATORY DIAGNOSIS:  TRADITIONAL WET PREPARATION  ANTIGEN TEST

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PARASITE: Iodamoeba buetschlii  Sluggishly and progressive  Pseudopodia blunt and hyaline  Inclusions: Bacteria but NO RBC  1 large nucleus  WITH GLYCOGEN MASS  Thick membrane INFECTIVE STAGE: CYST DIAGNOSTIC STAGE: CYST OR TROPHOZOITES ON OVA AND PARASITE EXAM

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PARASITE  Necator americanus MORPHOLOGY: LARVA DIAGNOSTIC STAGE: EGGS IN FECES RHABDITIFORM - Feeding Larva (L1) Molting 2x (L2) FILARIFORM  Infective stage (L3)  Adult form of Larva  Requires the pulmonary circulation to survive  Stays in the alveolar capillaries  SMALL INTESTINE o maturation, differentiation and reproduction PATHOLOGY:  Skin penetration  Vascular/lymphatic penetration  Pulmonary circulation (alveolar capillaries and rupture)  GIT then eggs in stool DIAGNOSTIC TEST: SUCKING BLOOD:  Necator (0.15 to 0.25 ml/day/parasite)  Duodenale (0.30 - 0.50 ml/day/parasite) TREATMENT: Mebendazole and Pyrantel Palmoate

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PARASITE  Ancylostoma braziliense o CAT HOOKWORM o Cutaneous larva migrans (CLM) o ”Creeping eruption” o Never leave the skin

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BUCCAL CAVITY – 2 UNEVEN PAIRS of teeth DIAGNOSTIC STAGE: FILARIFORM INFECTIVE STAGE: FILARIFORM (L3) DISEASE : Cutaneous Larva Migrans  Erythematous and Itchy  Pinpoint lesion  Map-like lesion LIFE CYCLE: Filariform Larva Only DEFINITIVE HOST: CAT DIAGNOSTIC TEST: Skin Biopsy TREATMENT:  Mebendazole

PARASITE  Ancylostoma caninum o DOG HOOKWORM o Creeping eruption o Never leave the skin BUCCAL CAVITY – 3 PAIRS of teeth DIAGNOSTIC STAGE: FILARIFORM INFECTIVE STAGE: FILARIFORM (L3) DEFINITIVE HOST: DOG PATHOLOGY: Cutaneous Larva Migrans (CLM)  Erythematous and Itchy  Pinpoint lesion  Map-like lesion INFECTIVE STAGE: Filariform Larva (L3) LIFE CYCLE: Filariform Larva Only DIAGNOSTIC TEST: Skin biopsy TREATMENT: Thiabendazole

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PARASITE  Trichuris trichiura (Egg)  Whipwhorm  Barrel/Lemon/Football-shape  With bacillary band INFECTIVE STAGE: FULLY EMBRYONATED EGG DIAGNOSTIC STAGE: FERTILIZED EGG DISEASE: Intestinal obstruction / Allergy DIAGNOSTIC TEST: Direct fecal smear TREATMENT: Mebendazole

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PARASITE  Trichinella spiralis(Encysted larva) o Hook worm o In the muscle o Encyst or developed only in Striated muscle o No egg stage o Trichina worm - Dead end alley infection (Cannot be transmitted from human to human) – ACCIDENTAL HOST: HUMAN HABITAT: Striated muscles (Skeletal muscles) ENCYSTATION: Upper Small Intestine REPRODUCTION: after mating, males die afterwards and females dies after passing the larva INFECTIVE STAGE: ENCYSTED LARVA DIAGNOSTIC: Muscle biopsy MOT: Ingestion of infected muscle with encysted larva TREATMENT:  Mebendazole: Kills the larva  Thiabendazole: Expels the adult worm

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PARASITE  Trichinella spiralis(Adult female)  Trichina worm  No egg  “dead-end alley” infection  Male (mates once, dies); female(pass larva, dies) PERMANENT HABITAT: Skeletal muscle (Striated muscle) DISEASE: Trichiniasis INFECTIVE STAGE: ENCYSTED LARVA DIAGNOSTIC TEST: Muscle biopsy MOT: Ingestion of infected muscle with encysted larva DEFINITIVE HOSTS: Carnivorous or Omnivorous animals (Cats, Dogs, Hogs, Rats, etc.) ACCIDENTAL HOST: Humans (cannot be transmitted from human to human) PATHOGNOMONIC: With STICHOSOME (Stichocytes – nerve cells) TREATMENT: Thiabendazole - Expels the adult worm

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PARASITE  Capillaria philippinensis (Pudoc worm)  EGGS: - Typical - yellow, moderately thick shell with striations, with flattened bipolar plug, peanut shaped Atypical – thin shelled, without bipolar plugs, with segmentation, embryonated INTERMEDIATE HOST: Freshwater fish INFECTIVE STAGE: Larva MOT: eating of infected fish with larva stage HABITAT: Jejunum DIAGNOSTIC STAGE: typical and atypical eggs in the feces DIAGNOSTIC TEST: DIRECT FECAL SMEAR SYMPTOMS: • Intestinal malabsorption (outstanding sign), worst symptom among aphasmids • Fat malabsorption • Fluid and electrolyte losses • Free passage of plasma protein • Abdominal pain and distention • Cachexia and emancipation TREATMENT: Mebendazole

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PARASITE  Strongyloides stercoralis(Filariform larva) o THREADWORM o POINTED o BUCCAL CAVITY: No teeth nor plates o DOESN’T REQUIRED HUMID SOIL INFECTIVE STAGE: FILARIFORM (L3) – Molts 4 times DISEASE: Conchin china diarrhea LIFE CYCLE:  4x molting  Pulmonary circulation  Auto reinfection  Manifest HYPERINFECTION MOT: Skin Penetration HABITAT: Small intestine, invade the mucosa up to muscularis layer but not the serosal layer DIAGNOSTIC STAGE: EGGS + RHABDITIFORM LABORATORY: Stool exam, Duodenal & Sputum examination POPULATION AFFECTED: Adults Institutionalized people TREATMENT: Thiabendazole

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PARASITE  Strongyloides stercoralis (Rhabditiform larva) o THREADWORM o STOUTER o BUCCAL CAVITY: No teeth nor plates o DOESN’T REQUIRED HUMID SOIL INFECTIVE STAGE: FILARIFORM LARVA (L3) DISEASE: Conchin china diarrhea LIFE CYCLE:  4x molting  Pulmonary circulation  Auto reinfection  Manifest HYPERINFECTION MOT: Skin Penetration HABITAT: Small intestine, invade the mucosa up to muscularis layer but not the serosal layer DIAGNOSTIC STAGE: EGGS + RHABDITIFORM LABORATORY: Stool exam, Duodenal & Sputum examination POPULATION: Adult, institutionalized patient TREATMENT: Thiabendazole

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PARASITE  Enterobius vermicularis (Adult female)  PINWORM & SEAT WORM  Presence of with CEPHALIC ALAE & ESOPHAGEAL BULB  Gravid female worms migrate down the intestinal tract and exist through the anus to deposit eggs on the perianal skin  After deposition, FEMALE DIES DISEASE: Oxyuriasis/Enterobiasis COMPLICATION:  Appendicitis  Vaginitis  Endometritis  Salpingitis  Peritonitis INFECTIVE STAGE: EMBRYONATED EGGS DIAGNOSTIC STAGE: ADULT WORM OR EGG PATHOLOGIC STAGE: ADULT PATHOLOGY: Bleeding diarrhea and prolapsed rectum DIAGNOSTIC TEST: Scotch adhesive tape swab – demonstrate embyonated ova MOT: Self-infection, Person to person, Airborne TREATMENT: Pyrantel Pamoate and Mebendazole (alternative)

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PARASITE  Enterobius vermicularis (Eggs)  Most common helminthic infection  One side flattened, other is convex  Oxyuris Vermiculris, Pinworm, Seatworm INFECTIVE STAGE: EMBRYONATED EGGS DIAGNOSTIC STAGE: ADULT WORM OR EGG  One side flattened and the other side convex (D-shaped)  Shell has 2 layers  Shape is planoconvex  Contains embryo RHABDITIFORM LARVA : 140-150 µm by 10 µm  Esophageal bulb but has no cuticular expansion on the anterior end. MOT: Self infection, Person to person, Airborne DIAGNOSTIC TEST: Scotch adhesive tape swab – demonstrate embyonated ova TREATMENT: Mebendazole and Pyrantel pamoat

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PARASITE  Toxocara canis  Toxocara canis cervical alae is longer than broader compared to Toxocara cati  Subglobose, moderately thick, coarsely pitted eggshell DEFINITIVE HOST: DOG INFECTIVE STAGE: EGG PATHOLOGIC STAGE: LARVA ACCIDENTAL HOST: HUMANS TWO MAIN CLINICAL PRESENTATIONS:  Visceral larva migrans – common in Preschool children  Ocular larva migrans DIAGNOSIS: TISSUE BIOPSY /ELISA MOT:  By ingesting infective stage eggs from soil  By ingesting larvae in tissues of paratenic hosts that were infected from soil or by cannibalism or predation TREATMENT: Albendazole and Mebendazole

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PARASITE  Ascaris lumbricoides (Fertilized egg)  Giant Intestinal Roundworm parasitizing human  Golden brown in color  Brodly ovoid with thick and transparent shell  WITH VITELLINE LAYER (Innermost layer) AND MAMMILATIONS DISEASE: ASCARIASIS, LOEFFLER SYNDROME DEFINITIVE HOST: HUMAN INFECTIVE STAGE: FULLY EMBRYONATED EGG PATHOGENIC STAGE: Adult, Larva ADULTS: 3 prominent lips , Each with dentigenous ridge and no interlabia or alae DIAGNOSTIC EXAMS:  Direct fecal smear  Demonstration of eggs in feces TREATMENT: Mebendazole – Drug of choice

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PARASITE  Ascaris lumbricoides (UNFertilized egg)  Most common human helminthic infection MORPHOLOGY:  Egg-thick shelled CLINICAL MANIFESTATION:  ADULT WORMS usually causes NO SYMPTOMS  Loeffler’s syndrome (Cough, dyspnea, hemoptysis and eosinophilic pneumonitis) DEFINITIVE HOST: HUMAN INFECTIVE STAGE: FULLY EMBRYONATED EGG DIAGNOSIS:  Direct Fecal Smear  Demonstration of eggs in feces TREATMENT: Mebendazole/Albendazole

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PARASITE: Brugia malayi  NOTE: two terminal nuclei (posterior end diagnostic) PERIODICITY: Nocturnal (10pm-2am) DISEASE: Lymphatic filariasis INTERMEDIATE HOST: Mansonia DIAGNOSIS:  Giemsa stained thick blood film (must be drawn at Night, 10 pm – 2am) STAGE: Microfilaria ] DIAGNOSTIC INFECTIVE STAGE: FILARIFORM LARVA (L3)

LIFE CYCLE: Circulate from 10pm - 2am (nocturnal), mosquito ingest the microfilaria (3rd stage juvenile larva), larva then matures to adult in the lymphatics TREATMENT: Diethylcarbamazine, Albendazole and Ivermectin (alternative)

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PARASITE: Wuchercheria bancrofti DISEASE: Lymphatic filariasis DIAGNOSTIC STAGE: MICROFILARIA INFECTIVE STAGE: L3 LARVA VECTOR: Anopheles, Culex, Aedes DIAGNOSIS:  Giemsa stained thick blood film (must be drawn at Night, 10 pm – 2am) TREATMENT: Diethylcarbamazine

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DISEASE INTERMEDIATE HOST DIAGNOSTIC STAGE INFECTIVE STAGE PERIODICITY BODY CURVES PRESENCE/ABSENCE OF TRANSPARENT SHEATH ARRANGEMENT OF BODY NUCLEI DIAGNOSTIC EXAM DRUG OF CHOICE

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Lymphatic Filariasis Anopheles, Culex, Aedes Microfilariae L3 Nocturnal Graceful curves, bluntly rounded anterior and pointed posterior (+)

Lymphatic Filariasis Mansonia Microfilariae L3 Nocturnal Stiff, kinky body

Central column are more or less equidistant with each other Devoid terminal nuclei

Large with irregular distribution appear clumped Long cephalic space Devoid of nuclei Giemsa stained thick blood smear Diethylcarbamazine

Giemsa stained thick blood smear Diethylcarbamazine

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PARASITE: Echinococcus granulosus  SMALLEST TAPEWORM of medical importance  SCOLEX with prominent rostellum  DOUBLE CROWN of hooks  NO adult form in humans  Short with 3 proglottids with o 1 IMMATURE o 1 MATURE o 1 GRAVID INFECTIVE STAGE: HYDATID CYST HABITAT: Small intestine of dogs and wolves DEFINITIVE HOST: Dogs and Wolves INTERMEDIATE HOST: Sheep and Cattle DISEASE: HYDATID DISEASE MOT: INGESTION MOST COMMON ORGAN AFFECTED: LIVER TREATMENT: Surgery Epinephrine and Anti histamine LABORATORY DIAGNOSIS:  Finding proctoscolices, brood capsules or daughter cyst  ELISA

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PARASITE: Hymenolepsis nana  DWARF TAPEWORM  SCOLEX: SHORT retractile rostellum with SINGLE ring of small hook  MATURE PROGLOTTID: Single genital pore on LEFT SIDE  EGG: Oval encloses HEXACANTH embryo, inner membrane has 2 POLAR THICKENINGS

NO INTERMEDIATE HOST!! INFECTIVE STAGE: CERCOCYTIS DIAGNOSTIC STAGE: EGGS WITH 6 HOOKLETS IN THE FECES HABITAT: ILEUM DEFINITIVE HOST: HUMAN, MICE AND RATS MOT: INGESTION TREATMENT: PRAZIQUANTE

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PARASITE: Hymenolepsis diminuta  SCOLEX: UNARMED ROSTELLUM  GRAVID PROGLOTTID: Contains SACCULAR UTERUS with EGG MASSES  EGG: NO POLAR FILAMENTS OR THICKENINGS

INFECTIVE STAGE: CERCOCYSTIS DIGNOSTIC STAGE: UNEMBRYONATED EGG DISEASE: HABITAT: ILEUM DEFINITIVE HOST: RATS AND MICE INTERMEDIATE HOST: Larval Fleas and Adult beetles ACCIDENTAL HOST: Human MOT: Ingestion TREATMENT: PRAZIQUANTEL

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PARASITE: Diphyllobothrium caninum  DOG TAPEWORM  AKA DOUBLE-PORED TAPEWORM  GRAVID PROGLOTTID: Packed with MEMBRANOUS EGG CAPSULES containing 15-25 eggs  EGGS: Oncosphere with 6 hooklets  GENITAL PORE located BILATERALLY  Proglottid is watermelon shape DISEASE: DIPYLIDIASIS INFECTIVE STAGE: CYSTICERCOID LARVA DIGNOSTIC STAGE: EGGS IN MOTHER POCKETS HABITAT: SMALL INTESTINE DEFINITIVE HOST: DOGS INTERMEDIATE HOST: LARVAL FLEAS of dogs ands cats MOT: Ingestion TREATMENT: PRAZIQUANTEL

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PARASITE: Diphyllobothrium latum  FISH TAPEWORM  JEWISH HOUSEWIVES DISEASE  SCOLEX: 2 BOTHRIUM OR SUCKING ORGAN  MALE ORGAN: DORSAL PART OF PROGLOTTID  FEMALE ORGAN: VENTRAL PART  ASSOCIATED WITH PERNICIOUS ANEMIA DISEASE: DIPHYLLOBOTRIASIS INFECTIVE STAGE: PLEROCERCOID LARVAE (SPARGANUM) DIGNOSTIC STAGE: UNEMBRYONATED EGG NOURISHMENT:DIFFUSION from undigested food of the host HABITAT: ILEUM DEFINITIVE HOST: INTERMEDIATE HOST: 1ST: COPEPODS 2ND: FISH ACCIDENTAL HOST: HUMAN MOT: INGESTION TREATMENT: NICLOSAMIDE

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PARASITE: Taenia solium  PORK TAPEWORM DISEASE: CYSTERCOSIS INFECTIVE STAGE: ADULT WORM DIGNOSTIC STAGE: EGGS OR PROGLOTTIDS IN FECES HABITAT: UPPER PART OF JEJUNUM DEFINITIVE HOST: MAN LIFE SPAN: 25 YEARS INTERMEDIATE HOST: HOGS AND WILD BOARS 1ST: COPEPODS 2ND: FISH MOT: INGESTION OF RAW PORK DIAGNOSTIC TEST:  Stool examination (Identification of ovum ang segments in feces TREATMENT: NICLOSAMIDE

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PARASITE: Fasciola hepatica  SHEEP LIVER FLUKE  LARGE LEAF SHAPE  Live as long as 11 years DISEASE: FASCIOLIASIS INFECTIVE STAGE: METACERCARIA SEX: MONOECIOUS DIGNOSTIC STAGE: EGG HABITAT: LIVER DEFINITIVE HOST: SHEEP ACCIDENTAL HOST: Human INTERMEDIATE HOST: 1ST – SNAIL 2ND – WATER CHESTNUTS & KANGKONG MOT: INGESTION

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INFECTIVE STAGE: CYSTICERCUS (CELLULOSAE/BOVIS) DIAGNOSTIC STAGE: EGGS AND GRAVID PROGLOTTIDS

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PARASITE: Clonorchis sinensis  CHINESE LIVER FLUKE / ORIENTAL LIVER FLUKE  LANCET SHAPE  Excyst in the LIVER  Adult worms can LIVE UP TO 25 YEARS  With TWO LARGE AND DEEPLY LOBED TESTES situated one behind the other. DISEASE: CHLONORCHIASIS INFECTIVE STAGE: METACERCARIA DIAGNOSTIC STAGE: Unembryonated egg SEX: MONOECIOUS HABITAT: LIVER DEFINITIVE HOST: MAN INTERMEDIATE HOST: 1ST: OPERCULATED SNAIL 2ND: FRESHWATER FISH

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PARASITE: Paragonimus westermani  ORIENTAL LUNG FLUKE  EGG: Flat operculum, thickening at base – chocolate or color brown in color  TESTES – DEEPLY LOBED SIDE BY SIDE DISEASE: PARAGONIMIASIS CLINICAL MANIFESTATION:  PLEURITIC PAIN INFECTIVE STAGE: METACERCARIA DIAGNOSTIC STAGE: UNEMBRYONATED EGG SEX: MONOECIOUS HABITAT: LUNG DEFINITIVE HOST: MAN INTERMEDIATE HOST: 1ST: SNAIL 2ND: CRAB/CRAYFISH DIAGNOSTIC EXAM:  Chest xray  Identification of egg: STOOL AND SPUTUM EXAM TREATMENT: PRAZIQUANTEL

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PARASITE: Echinostoma ilocanum  GARRISON’S FLUKE  TESTES: Deeply lobed, in tandem  “GERM YOLK” big mass of yolk  Small and slightly triangular operculum One end is ovoid, attenuated and the other is more rounded and straw-colored DISEASE: ECHINOSTOMIASIS INFECTIVE STAGE: METACERCARIA DIAGNOSTIC STAGE: LARGE OPERCULATED EGG HABITAT: INTESTINE INTERMEDIATE HOST: 1ST: SNAIL 2ND: FRESHWATER MOLLUSC

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PARASITE: FORK TAILED CERCARIA  DIOCEIOUS  NO REDIA STAGE  EGGS: MATURE, NON OPERCULATED  Final free-swimming larval stage of a TREMATODE/FLUKE  Consisting of a body and tail  Infective stage of BLOOD FLUKES/Schistosomes

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PARASITE: Schistosoma mansoni -EGG DISEASE: SCHISTOSOMIASIS DEFINITIVE HOST: MAN INFECTIVE STAGE: CERCARIA DIAGNOSTIC STAGE: EGG SEX: DIOECIOUS 1ST INTERMEDIATE HOST: SNAIL 2ND INTERMEDIATE HOST: NONE

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PARASITE: Schistosoma japonicum in copula DISEASE: SCHISTOSOMIASIS DEFINITIVE HOST: MAN INFECTIVE STAGE: CERCARIA DIAGNOSTIC STAGE: EGG SEX: DIOECIOUS 1ST INTERMEDIATE HOST: SNAIL 2ND INTERMEDIATE HOST: NONE

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PARASITE: Ctenocephalides canis – DOG FLEA DISEASE: IH of MINOR CESTODES:  Dipylidium caninum and Hymenolepis nana

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PARASITE: Taenia solium STAGE: Cysticercus cellulosae INFECTIVE STAGE: CYSTICERCUS CELLULOSAE DIAGNOSTIC STAGE: EGGS AND GRAVID PROGLOTTIDS

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INFECTIVE STAGE: METACERCARIAE DIAGNOSTIC STAGE: UNEMBRYONATED EGG  Moderately fleshy  Relatively flat, leaf-like  Highly dendritic intestinal ceca, vitellaria and testis  ANT. PART: CEPHALIC CONE  POST. PART: BROADLY POINTED

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INFECTIVE STAGE: CYSTICERCUS (CELLULOSAE/BOVIS) DIAGNOSTIC STAGE: EGGS AND GRAVID PROGLOTTIDS

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